SendGrid Email Destination

When to use this destination type

Choose SENDGRID_EMAIL when the receiver target is SendGrid Mail Send API. Destinations are outbound delivery targets: they do not decide whether a source request should be accepted, and they do not own connection filters or transformations. They own where the final delivery goes and how FastHook should authenticate, pace, disable, and inspect that delivery.

A destination can be reused by multiple connections when several source branches should feed the same receiver. Reuse keeps receiver capacity, credentials, and attempt evidence attached to one destination id.

FastHook dashboard fields

In the dashboard, create a destination, set Destination Type to SENDGRID_EMAIL, then fill the fields below.

API config fields

The REST API stores destination-specific behavior under config. Use PATCH for focused edits and PUT only when your request contains the full config you want to keep.

{
  "name": "ops-sendgrid-alerts",
  "type": "SENDGRID_EMAIL",
  "config": {
    "from": "alerts@example.com",
    "from_name": "FastHook Alerts",
    "to": [
      "ops@example.com",
      "{{payload.owner.email}}"
    ],
    "cc": [
      "support@example.com"
    ],
    "subject": "FastHook event {{event_id}}",
    "text_template": "A webhook event needs review.\n\n{{payload}}",
    "html_template": "<pre>{{payload}}</pre>",
    "reply_to": "support@example.com",
    "api_base_url": "https://api.sendgrid.com",
    "auth_type": "SENDGRID_API_KEY",
    "auth": {
      "api_key": "SG.your-sendgrid-api-key"
    },
    "rate_limit": 1,
    "rate_limit_period": "second"
  }
}

curl -X POST "https://api.fasthook.io/v1/destinations" \
  -H "Authorization: Bearer $FASTHOOK_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "name": "ops-sendgrid-alerts",
  "type": "SENDGRID_EMAIL",
  "config": {
    "from": "alerts@example.com",
    "from_name": "FastHook Alerts",
    "to": [
      "ops@example.com",
      "{{payload.owner.email}}"
    ],
    "cc": [
      "support@example.com"
    ],
    "subject": "FastHook event {{event_id}}",
    "text_template": "A webhook event needs review.\n\n{{payload}}",
    "html_template": "<pre>{{payload}}</pre>",
    "reply_to": "support@example.com",
    "api_base_url": "https://api.sendgrid.com",
    "auth_type": "SENDGRID_API_KEY",
    "auth": {
      "api_key": "SG.your-sendgrid-api-key"
    },
    "rate_limit": 1,
    "rate_limit_period": "second"
  }
}'

Authentication

Destination authentication is outbound. It helps the receiver trust or accept FastHook delivery, and it is separate from source authentication that verifies the original webhook producer.

• SendGrid API key with Mail Send access
• Verified SendGrid sender identity or authenticated sending domain

HTTP methods and rate limit

This destination type uses the methods below for delivery attempts. Rate limits apply at the destination boundary, so every connection that targets the same destination shares that capacity.

Rate limit: Locked to 1 request per second.

Delivery behavior

• FastHook renders recipient, subject, text, and HTML templates per delivery, then sends through SendGrid's Mail Send API.
• SendGrid returns HTTP 202 when the message is accepted for processing. Final delivery, bounce, block, or spam placement is tracked in SendGrid activity and events.
• The From address must be a SendGrid verified sender identity or belong to an authenticated sending domain.
• FastHook blocks fasthook.io and subdomains for normal users so customer accounts cannot send as FastHook; FastHook admins can use them for system messages.
• A single rendered delivery can include up to 10 total To, Cc, and Bcc recipients.
• SendGrid Email destinations are locked to 1 request per second to reduce accidental email bursts.

Setup checklist

1. Open SendGrid and verify a Single Sender identity or authenticate a sending domain.
2. Create a SendGrid API key with Mail Send permission.
3. Create a FastHook destination and choose SENDGRID_EMAIL as the destination type.
4. Set From email to the verified sender or authenticated domain address. Use fasthook.io only for FastHook admin-owned system destinations.
5. Set To recipients, subject, text body, and optional HTML body. Use template tokens only where the rendered values are valid email content.
6. Choose the US or EU SendGrid API region that matches the SendGrid account.
7. Paste the SendGrid API key, then connect only email-worthy events through filters.

Troubleshooting

Related docs

• Destinations
• Filter and route events
• Control throughput
• SendGrid Mail Send API
• SendGrid sender identity
• SendGrid domain authentication
• API reference